1Universität Wien Abteilung für Sportmedizin, Leistungsphysiologie und Prävention, Zentrum für Sportwissenschaft und Universitätssport Wien, Österreich; 2Universität Wien Institut für analytische Chemie, Fakultät für Chemie Wien, Österreich
Background
Three-dimensional echocardiography (3D) is a valuable tool for assessing physiological adaptations of the athlete’s heart. However, different company-specific echocardiographic systems can be used and specific normal values for recent automated methods are still rare for young and healthy individuals and vary with the manufacturer of the echocardiographic device. The aim of this study was to quantify automated LV and RV volumes with Philips EPIQ CVx in young and healthy individuals with different fitness levels to analyze effects of endurance training on RV and LV and its relation to V̇O2max.
Methods
162 males (27 ± 5 years) and 130 females (26 ± 4 years), ranging from recreationally active individuals to competitive athletes, participated in the study. Echocardiography was conducted with Philips EPIQ CVx to quantify 3D LV and RV end-diastolic volumes (3D LVEDV, 3D RVEDV) offline by Philips QLAB using Dynamic HeartModelA.I. for LV and 3D Auto RV for RV. In addition, LV and RVEDV were indexed to body surface area and 3D LV/RV EDV ratio was calculated. Spiroergometry was performed to determine VO2max to categorize endurance fitness levels into three groups: untrained (U), moderately endurance-trained (M), and endurance-trained (E). As cut-off served the 25th and 75th percentiles of V̇O2max.
Results
Table 1: Sex-specific V̇O2max and 3D-volume values
|
Sex |
VO2max (ml/min/kg) Mean (95%CI) |
LVEDV (ml) Mean (95%CI) |
LVEDVi (ml/m2) Mean (95%CI) |
RVEDV (ml) Mean (95%CI) |
RVEDVi (ml/m2) Mean (95%CI) |
LV/RV Ratio Mean (95%CI) |
|
Female |
48 (47-49) |
133 (129-136) |
79 (76-81) |
117 (114-121) |
70 (68-72) |
1.1 (1.1-1.2) |
|
Male |
54 (53-56) |
177 (173-182) |
90 (89-92) |
163 (159-168) |
83 (81-86) |
1.0 (1.0-1.1) |
In all fitness categories males (m) compared to females (f) showed significantly higher 3D LV and RV EDV and EDVi (p<0.001). The E group compared to the U group demonstrated significantly higher 3D LVEDVi (m: +13 (95% CI 8-18) ml/m2; f: +14 (95% CI 9-19) ml/m2) and 3D RVEDVi (m: +12 (95% CI 5-20) ml/m2; f: +8 (95% CI 2-14) ml/m2) in both sexes (p<0,05), while the 3D LV/RV ratio remained constant in all groups (p<0,05).
Table 2: 3D-volumes categorized by fitness levels
|
Fitness level |
Sex |
VO2 max (ml/min/kg), Median (IQR) |
LV (ml/m2) Mean (95% CI) |
RV (ml/m2) Mean (95% CI) |
LV/RV Ratio Mean (95% CI) |
|
Untrained
|
Female |
41 (3) |
72 (69-76) |
67 (63-70) |
1.1 (1.0-1.2) |
|
Male |
46 (5) |
86 (82-90) |
78 (74-82) |
1.1 (1.1-1.2) | |
|
Moderately endurance-trained
|
Female |
48 (4) |
80 (76-82) |
70 (67-73) |
1.2 (1.1-1.2) |
|
Male |
55 (5) |
89 (86-91) |
83 (80-86) |
1.1 (1.1-1.1) | |
|
Endurance-trained
|
Female |
56 (3) |
86 (83-90) |
75 (71-78) |
1.1 (1.1-1.2) |
|
Male |
63 (5) |
99 (95-103) |
90 (86-95) |
1.1 (1.1-1.2) |
Correlation of 3D LVEDVi (m: r=0.386; f: r=0.553) and 3D RVEDVi (m: r=0.283; f: 0.316) with VO2max showed weak to moderate associations in both sexes (p<0.001).
Conclusion
This study shows significant differences in absolute and indexed 3D LV and RVEDV between both sexes at all fitness levels. With elevated endurance fitness LV and RVEDV were significantly higher at both sexes with constant 3D LV/RV ratios over all groups, which supports the hypothesis of a balanced and harmonic LV and RV endurance-induced eccentric hypertrophy of the athlete’s heart analyzed by recent automated echocardiographic algorithms. Furthermore, normal ranges for LV and RVEDV of this study can be used for method- and fitness-specific normal reference values in young, healthy individuals and contribute to an adequate evaluation of the athlete’s heart.